code: def testDC(self):
      # input is [1, 0, 0, ...] which corresponds to an IFFT of constant magnitude 1
      signalSize = 512
      fftSize = int(signalSize / 2) + 1
  
      signalDC = zeros(signalSize)
      signalDC[0] = 1.0
  
      fftInput = [1 + 0j] * fftSize
  
      self.assertAlmostEqualVector(
          signalDC * signalSize, IFFT(normalize=False)(cvec(fftInput))
      )
  
file_path: essentia/test/src/unittests/standard/test_ifft.py
imports: from essentia_test import *
  import math
label_desc: Use image node_id 1 for calling the TestIFFT obj's underlying member method code with example usage: obj.testDC() without return types